Gas turbine engine



March 9, 1965 R. CHUTE 3,172,260

GAS TURBINE ENGINE Filed Nov. 15, 1961 2 Sheets-Sheet l INVENTOR. I?! amRD CHUTE ATTO RNEYS March 9, 1965 R. CHUTE 3,172,260

GAS TURBINE ENGINE Filed Nov. 13. 1961 2 Sheets-Sheet 2 mmvroa. P/c'HA/wCHUTE ATTO RN EYS United States Patent 3,172,260 GAS TURBINE ENGINERichard Chute, Huntington Woods, Mich, assignor to Continental MotorsCorporation, Muskegon, Mich., a corporation of Virginia Filed Nov. 13,1961, Ser. No. 151,931 Claims. (Cl. oil-39.75)

This invention relates to gas turbine engines and more particularly to acompact, dual stage turbine unit utilizing back to back radial flowcompressors and turbine wheels.

The present emphasis on turbine engine development has produced a needfor a compact, efiicient turbine power plant. Heretofore, duct work haspresented one of the biggest obstacles in designing such a unit. Thepresent invention minimizes the ductwork necessary in a dual stageturbine engine by a unique arrangement of necessary components.

It is an object of the present invention to minimize the spacerequirements of a dual stage gas turbine engine by arranging thenecessary components so as to produce a compact unit.

It is a further object of the present invention to reduce manufacturingcosts of a turbine engine by providing a simply constructed, low loss,two stage unit.

A further object of the invention is to produce a compact dual-stagedturbine system having efiicient and smooth gas flow characteristics.

Further objects and advantages will be apparent to one skilled in theart to which the invention pertains upon reference to the followingdrawings illustrating preferred embodiments of the invention in whichlike characters refer to like parts throughout the several views and inwhich:

FIG. 1 is a longitudinal cross sectional view of a preferred embodimentof the present invention.

FIG. 2 is a cross sectional view similar to FIG. 1 but showing anotherpreferred embodiment of the present invention, and

FIG. 3 is a cross-sectional view taken substantially on the line 33 ofFIG. 2.

Referring now to the drawings for a more detailed description of thepresent invention, FIG. 1 shows a gas turbine engine 10 as comprising aturbine unit 11 and a compressor unit 12 carried at opposite ends of ashaft 13. A burner unit 14 is disposed intermediate the compressor unit12 and the turbine unit 11.

The compressor unit 12 comprises a compressor housing 15 rotatablycarrying the shaft 13 by means of bearings 13A carried at the inner endof the compressor housing 15. The compressor housing 15 is provided withan air intake port 17. Air enters the port 17 as indicated by the arrowsbeginning at A in FIG. 1, and is directed by stator vanes 18 into theradial flow impeller vanes 19 carried on a wheel 20 secured to the endof the shaft 13. The air as compressed leaves the tips of the vanes 19and flows past diffuser vanes 19A into a toroidal chamber 21 provided inthe compressor housing 15 and which is substantially concentric to theradial flow wheel 20.

The air passes arcuately through the chamber 21 and is directed by asecond set of stator vanes 23 into the path of radial flow impellervanes 24 of a second radial flow wheel 25. The radial flow wheel 25 isconstructed substantially the same as the wheel 20 and is secured to theshaft 13 in back to back relation with the wheel 20. The air, atincreased pressure, flows into a central toroidal chamber 22.

The compressed air passes through a compressed multiple air outlet port29 provided in the compressor housing 15 and into air duct 30 to theburner unit 14.

The portions of the compressor housing 15 which form the toroidalchambers 21 and 22 are preferably strengthened and supported byannularly spaced through bolts 27 or similar means. Labyrinth seals 28prevent leakage of the compressed air along the rotating shaft 13.

The burner unit 14 comprises a burner housing 31 enclosing a compressedair chamber 32 which in turn encompasses a burner liner 33 defining acombustion chamber 34. The burner housing 31 is provided with acompressed air inlet port 35 communicating with the air duct 30. Thecompressed air passes through the inlet port 35 into the compressed airchamber 32 and through ports 36 provided in the burner liner 33 into thecombustion chamber 34. A fuel nozzle 37 sprays fuel into the chamber 34and an igniter plug 38 provides ignition to the fuel-air mixture. Thecombustion gases are directed by a gas duct 39 to the turbine unit 11.

The turbine unit 11 comprises a turbine housing 40 rotatably carryingthe shaft 13 by means of bearings 41 at an end of the shaft opposite theposition of the compressor housing 15. The turbine housing 40 defines atoroidal chamber 42 which is like the chamber 21. The housing 40 isprovided with an exhaust gas inlet 45 which provides communicationbetween the exhaust gas duct 39 and a central toroidal chamber 44. Theexhaust gases are directed from the chamber 44 radially inwardly intothe path of a radial inflow turbine wheel 46 secured to the shaft 13.Rotative force applied to the wheel 46 by the gases is utilized to turnthe shaft 13 and thus rotate the compressor wheels 20 and 25.

Since energy still remains in the exhaust gases, they are directed by aset of stator vanes 47 into the toroidal chamber 42 and from thereradially inwardly into the path of a second radial inflow turbine wheel48. The turbine wheels 46 and 48, like their counterparts compressorwheels 20 and 25, are secured to the shaft 13 in a back to backrelationship. The exhaust gases are now directed by a second set ofstator vanes 49 through an exhaust outlet port 50 provided in theturbine housing 40.

Like the compressor unit 12, the turbine unit 11 is also provided withlabyrinth seals 51 to prevent the escape of gases along the axis of theshaft 13. Also the housing 40 is provided with annularly spaced throughbolts 52 to add strength and to support the portions of the housing 40encompassing the toroidal chambers 42 and 44.

FIGS. 1 and 2 illustrate possible applications of the gas turbine engineof the present invention. In FIG. 1 the shaft 13 is geared as at 13B toprovide a power take off which may have many different uses. Such apower takeoff could be geared to the transmission of a vehicle or itcould be used to provide power to propel marine craft or aircraft. FIG.2 illustrates a generator 53 as having an armature 54 being rotated bythe shaft 13. It will be noted that this embodiment of the inventionprovides a very compact generator unit.

It is apparent from the foregoing description that the present inventionprovides a method of combining two radial flow compressors and tworadial flow turbines, producing a highly compact and efficient gasturbine engine. The reduction in the amount of ductwork required as wellas the space saved in positioning the compressor wheels and turbinewheels back to back has produced a unit which provides a very highhorsepower for the amount of space required and its total weight. Inaddition to permitting use of gas turbine engines in situations whereheretofore weight or space limitations were prohibitive, these featureshelp to reduce manufacturing and shipping costs.

Although I have described but a few embodiments of the invention, itwill be apparent to one skilled in vthe art to which the inventionpertains that various .2 changes and modifications may be made thereinwithout departing from the spirit of the invention as expressed by thescope of the appended claims.

I claim:

1. A gas turbine engine comprising (a) a shaft and means rotatablysupporting said shaft,

(b) a compressor unit carried at one end of said shaft,

(c) a turbine unit carried at the other end of said shaft,

(d) means providing communication between said compressor unit and saidturbine unit,

(2) a burner disposed in said communicating means intermediate saidcompressor unit and said turbine unit,

(7") said compressor unit comprising,

a toroidal air passage of spiral cross-section extending coaxially aboutsaid shaft,

first and second compressor wheels arranged in back-to-back relationwith their respective vanes spaced along said passage,

an air inlet at the outer end of said spiral encompassing said shaft anddelivering air to said first wheel, said first wheel then delivering theair to said second wheel, and

an air outlet at the inner end of said spiral receiving air from saidsecond wheel and delivering it to said communicating means.

2. The gas turbine engine as defined in claim 1 and in which saidturbine unit comprises (a) a toroidal passage of spiral cross-sectionextending coaxially about said shaft,

(b) an exhaust gas inlet at the inner end of said spiral receiving gasesfrom said communicating means,

() first and second turbine wheels carried on said shaft and havingtheir respective vanes spaced along said last passage, said firstturbine wheel receiving exhaust gases from said last inlet anddelivering it to said second turbine wheel, and

(d) an exhaust gas outlet at the outer end of said spiral receivingexhaust gases from said second turbine wheel.

3. The engine as defined in claim 1 and in which said shaft is furtherprovided with power takeoff means disposed intermediate said compressorand said turbine unit.

4. A gas turbine engine comprising (a) a shaft and means rotatablysupporting said shaft,

(b) a compressor unit carried at one end of said shaft,

(0) a turbine unit carried at the other end of said shaft,

(d) means providing communication between said compressor unit and saidturbine unit,

(e) a burner disposed in said communicating means' intermediate saidcompressor unit and said turbine unit, (f) said turbine unit comprisinga toroidal passage of spiral cross-section extending coaxially aboutsaid shaft, an exhaust gas inlet at the inner end of said spiralreceiving gases from said communicating means, first and second turbineWheels carried on said shaft and having their respective vanes spacedalong said last passage, said first turbine wheel receiving exhaustgases from said last inlet and delivering it to said second turbinewheel, an exhaust gas outlet at the outer end of said spiral receivingexhaust gases from said second turbine wheel. 5. A gas turbine enginecomprising (a) a shaft and means rotatably supporting said shaft, (b) acompressor unit carried at one end of said shaft,

4 (c) a turbine unit carried at the other end of said shaft, (d) meansproviding communication between said compressor unit and said turbineunit,

5 (e) a burner disposed in said communicating means intermediate saidcompressor unit and said turbine unit,

(f) said compressor unit comprising a toroidal air passage of spiralcross section extending coaxially about said shaft,

first and second axial-inflow radial-outflow compressor wheels arrangedin back-to-back relation with their respective vanes spaced along saidpassage,

an air inlet at the outer end of said spiral encompassing said shaft anddelivering air axially to said first wheel, said first wheel thendelivering the air axially to said second wheel, and

an air outlet at the inner end of said spiral receiving air radiallyfrom said said second wheel and delivering it to said communicatingmeans.

6. The gas turbine engine as defined in claim 5 and including powertakeoff means fixed to said shaft intermediate said compressor unit andsaid turbine unit.

7. The gas turbine engine as defined in claim 5 and in which saidturbine unit comprises (a) a toroidal passage of spiral cross-sectionextending coaxially about said shaft, (b) an exhaust gas inlet at theinner end of said spiral receiving gases from said communicating means,

(0) first and second radial-inflow axial-outflow turbine wheels carriedon said shaft and having their respective vanes spaced along said lastpassage, said first turbine wheel receiving exhaust gases radially fromsaid last inlet and delivering it radially to said second turbine wheel,and

(d) an exhaust gas outlet at the outer end of said spiral receivingexhaust gases axially from said second turbine wheel.

8. A gas turbine engine comprising (a) a shaft and means rotatablysupporting said shaft,

(b) a compressor unit carried at one end of said shaft,

H (c) a turbine unit carried at the other end of said shaft,

' (d) means providing communication between said compressor unit andsaid turbine unit,

(e) a burner disposed in said communicating means intermediate saidcompressor unit and said turbine unit,

(f) said turbine unit comprising a toroidal passage of spiralcross-section extending coaxially about said shaft, an exhaust gas inletat the inner end of said spiral receiving gases from said communicatingmeans,

first and second radial-inflow axial-outflow turbine wheels carried onsaid shaft and having their respective vanes spaced along said lastpassage, said first turbine wheel receiving exhaust gases radially fromsaid last inlet and delivering it radially to said second turbine Wheel,and

an exhaust gas outlet at the outer end of said spiral receiving exhaustgases axially from saidsecond turbine wheel. 9. In a gas turbine engineincluding a two-stage compressor, an air inlet for said compressor, andan outlet delivering air from said compressor to a burner, theimprovement comprising:

(a) a toroidal air passage of spiral cross-section in said compressor,

(b) each of the compressor wheels having vanes re- 5 spectively spacedin said passage,

(c) said air inlet being disposed at one end of said spiralling passage,and

(d) said air outlet being disposed at the opposite end of saidspiralling passage.

10. In a gass turbine engine including a two-stage tur- 5 blue, agas-exhaust inlet for said turbine, and a gasexhaust outlet for saidturbine, the improvement comprising:

(a) a toroidal passage of spiral cross-section in said turbine, 10

(b) each of the turbine wheels having vanes respectively spaced in saidpassage,

(0) said inlet being disposed at one end of said spiralling passage, and

(d) said outlet being disposed at the opposite end of 15 said spirallingpassage.

References Cited in the file of this patent UNITED STATES PATENTSBirmann June 22, 1948 Birmann June 14, 1949 einhardt Ian. 16, 1951Pavlecka Oct. 15, 1957 Hill Jan. 28, 1958 Sampietro July 18, 1961FOREIGN PATENTS Germany Feb. 23, 1923 Great Britain Dec. 10, 1948

1. A GAS TURBINE ENGINE COMPRISING (A) A SHAFT AND MEANS ROTATABLYSUPPORTING SAID SHAFT, (B) A COMPRESSOR UNIT CARRIED AT ONE END OF SAIDSHAFT, (C) A TURBINE UNIT CARRIED AT THE OTHER END OF SAID SHAFT, (D)MEANS PROVIDING COMMUNICATION BETWEEN SAID COMPRESSOR UNIT AND SAIDTURBINE UNIT, (E) A BURNER DISPOSED IN SAID COMMUNICATING MEANSINTERMEDIATE SAID COMPRESSOR UNIT AND SAID TURBINE UNIT, (F) SAIDCOMPRESSOR UNIT COMPRISING, A TOROIDAL AIR PASSAGE OF SPIRALCROSS-SECTION EXTENDING COAXIALLY ABOUT SAID SHAFT, FIRST AND SECONDCOMPRESSOR WHEELS ARRANGED IN BACK-TO-BACK RELATION WITH THEIRRESPECTIVE VANES SPACED ALONG SAID PASSAGE, AN AIR INLE AT THE OUTER ENDOF SAID SPIRAL ENCOMPASSING SAID SHAFT AND DELIVERING AIR TO SAID FIRSTWHEEL, SAID FIRST WHEEL THEN DELIVERING THE AIR TO SAID SECOND WHEEL,AND AN AIR OUTLET AT THE INNER END OF SAID SPIRAL RECEIVING AIR FROMSAID SECOND WHEEL AND DELIVERING IT TO SAID COMMUNICATING MEANS.